Cable harnesses include one or more connectors terminated to a multi-conductor cable. They are often manufactured by a work station that automatically terminates a desired number of connectors to the multi-conductor cable at desired locations along the cable. One work station of this type is described in detail in U.S. Pat. Nos. 4,903,403 and 4,870,752. To minimize waste of multi-conductor cable and connectors, the work station includes a testing system to test the cable harness at each step in its manufacture to insure that the connectors have been properly terminated and the multi-conductor cable is free of defects. When a defect is identified, the defective portions of the cable harness are rejected before further multi-conductor cable or connectors are added to the defective cable harness.
Each cable harness is manufactured so that for each conductor within the cable, there is a corresponding terminal electrically coupled thereto within each connector. Terminating the connectors results in corresponding terminals of each connector becoming electrically connected to a corresponding conductor within the multi-conductor cable.
Testing of each cable harness includes testing for shorts and for continuity. The "shorts" testing includes testing for electrical shorts between individual conductors in the multi-conductor cable and between terminals within the connectors. The continuity testing includes testing for continuity between each terminal and the conductor of the multi-conductor cable connected thereto. One common method of testing for continuity between two terminals and the intervening multi-conductor cable, is to short all of the terminals of one connector together and then apply a signal to one of the terminals of the unshorted connector.
If proper continuity exists, this signal travels along a conductor of the multi-conductor cable to the terminals of the connector that are shorted together and then back through the other conductors of the multi-conductor cable. If continuity exists, this signal is detected by appropriate sensors coupled to the terminals of the unshorted connector. By testing for continuity after each connector (excluding the first connector) is terminated, the cable harness may be rejected immediately upon the detection of lack of continuity and before further connector termination to the multi-conductor cable and waste of further connectors and multi-conductor cable.
Apparatus for shorting terminals together presently require that the work station utilize multiple tooling apparati for both termination and for shorting to test for continuity. In these work stations, a ram compresses a module surrounding a connector which has not yet been terminated. The connector has the multi-conductor cable passing therethrough. The ram causes tooling within the module to contact a housing of the connector, driving the housing and the terminals supported thereby toward a cover of the connector on a side of the multi-conductor cable opposite the housing.
This tooling applies a force to the housing sufficient to terminate the terminals to conductors within the cable and also cause the terminals to be connected to the cover. Simultaneously, shorting tooling within the module and adjacent the cover is forced into electrical connection with the terminals of the connector, causing the terminals to be shorted together. Thus, one tooling apparatus terminates the connector to the multi-conductor cable and a second tooling apparatus shorts the terminals together. After testing is complete, the ram is released and the termination tooling and the shorting tooling disengages from the terminals.
While this system effectively terminates and shorts the terminals together, it increases the number of tooling apparati necessary for work station operation. In addition, the shorting tooling is inherently delicate in that it must have probes passing through holes in the cover. This shorting tooling is thus subject to breakage or premature failure.